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Electronics => Beginners => Topic started by: J4e8a16n on January 27, 2014, 03:55:57 pm

Title: remote control works if no motor is running on the same 120 volts line
Post by: J4e8a16n on January 27, 2014, 03:55:57 pm
Hi,

I build this and it works. Here is the but.
If I am running on my treadmill.  It keeps false triggering like a ratle snake.

Any  clue?
Title: Re: remote control works if no motor is running on the same 120 volts line
Post by: Neilm on January 27, 2014, 07:16:10 pm
I would guess that the treadmill is putting pulses of noise onto the mains. This is then getting through your wall wart and introducing pulses onto your power supply. If the pulse is enough it will appear as if a pulse has been received.

I would try adding some more filtering to the supply input.
Title: Re: remote control works if no motor is running on the same 120 volts line
Post by: Dave on January 27, 2014, 07:51:47 pm
Hate to break it to you, but this schematic is terrible.
There is no need for current limiting in this circuit. You don't have any unknown loads on your supply line.
That TSOP17 IR receiver has an absolute maximum output current rating of 5mA, which is definitely exceeded when you are discharging a cap through it + shorting the supply rail through that PN junction of that PNP. The receiver could already be damaged.
The circuit reacts to pretty much any 38kHz IR signal. ANY. You threadmill could just be outputting an IR signal for some sort of isolated PC communication (kind of like the one you find on multimeters).

Use a small microcontroller (like a Tiny13) to decode the signal from the receiver and trigger the relay. A lot more reliable and you can also program the exact codes into it.
Title: Re: remote control works if no motor is running on the same 120 volts line
Post by: J4e8a16n on January 28, 2014, 01:55:45 pm
I gess both of you are right.

Is there adaptor for the motor to line?

I know almost nothing about pic...  Guess I will have to learn a bit of it.

Thanks.

JP
Title: Re: remote control works if no motor is running on the same 120 volts line
Post by: zapta on January 28, 2014, 04:19:06 pm
Cover the IR detector with opaque tape and run on batteries, do you still get false triggering?
Title: Re: remote control works if no motor is running on the same 120 volts line
Post by: J4e8a16n on January 28, 2014, 04:59:47 pm
Nope.
On battery, even if I dont cover the IR it does not false triggering. It just work.

Thanks for your free attention.
Title: Re: remote control works if no motor is running on the same 120 volts line
Post by: zapta on January 28, 2014, 07:19:44 pm
Quote from: J4e8a16n on January 28, 2014, 04:59:47 pm
Nope.
On battery, even if I dont cover the IR it does not false triggering. It just work.

Thanks for your free attention.

It looks then that the noise comes through the power supply. Try to add capacitors on the dc lines before and after the regullator.
Title: Re: remote control works if no motor is running on the same 120 volts line
Post by: J4e8a16n on January 28, 2014, 09:26:04 pm
Well...

I redid the test with the battery and it does trip.
Title: Re: remote control works if no motor is running on the same 120 volts line
Post by: Dave on January 28, 2014, 10:22:14 pm
Why even bother making a forum thread if you are just going to ignore the responses? ::)
Title: Re: remote control works if no motor is running on the same 120 volts line
Post by: J4e8a16n on January 28, 2014, 11:09:03 pm
Quote from: Dave on January 28, 2014, 10:22:14 pm
Why even bother making a forum thread if you are just going to ignore the responses? ::)
 

???

Quote
Cover the IR detector with opaque tape and run on batteries, do you still get false triggering?

I tried the capacitors.

then I redid (do again) the test with the battery and it does trip.

so I am lost.
Title: Re: remote control works if no motor is running on the same 120 volts line
Post by: J4e8a16n on January 29, 2014, 03:02:18 am
The transistor was damaged  while opening the casing. I replaced it.
So there is no tripping has before when I am on battery.
I added a capacitor before and after the regulator.

Here was the problem;
I putted back the metal box around the ir receptor.
It does work with the thredmill on the circuit.

Why?

Thanks for your help.